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| 1 | +# An example of semi-supervised node classification |
| 2 | + |
| 3 | +using Flux |
| 4 | +using Flux: onecold, onehotbatch |
| 5 | +using Flux.Losses: logitcrossentropy |
| 6 | +using GeometricFlux, GraphSignals |
| 7 | +using MLDatasets: Cora |
| 8 | +using Statistics, Random |
| 9 | +using CUDA |
| 10 | +CUDA.allowscalar(false) |
| 11 | + |
| 12 | +function eval_loss_accuracy(X, y, ids, model) |
| 13 | + ŷ = model(X) |
| 14 | + l = logitcrossentropy(ŷ[:,ids], y[:,ids]) |
| 15 | + acc = mean(onecold(ŷ[:,ids]) .== onecold(y[:,ids])) |
| 16 | + return (loss = round(l, digits=4), acc = round(acc*100, digits=2)) |
| 17 | +end |
| 18 | + |
| 19 | +# arguments for the `train` function |
| 20 | +Base.@kwdef mutable struct Args |
| 21 | + η = 1f-3 # learning rate |
| 22 | + epochs = 100 # number of epochs |
| 23 | + seed = 17 # set seed > 0 for reproducibility |
| 24 | + usecuda = true # if true use cuda (if available) |
| 25 | + nhidden = 128 # dimension of hidden features |
| 26 | + infotime = 10 # report every `infotime` epochs |
| 27 | +end |
| 28 | + |
| 29 | +function train(; kws...) |
| 30 | + args = Args(; kws...) |
| 31 | + |
| 32 | + args.seed > 0 && Random.seed!(args.seed) |
| 33 | + |
| 34 | + if args.usecuda && CUDA.functional() |
| 35 | + device = gpu |
| 36 | + args.seed > 0 && CUDA.seed!(args.seed) |
| 37 | + @info "Training on GPU" |
| 38 | + else |
| 39 | + device = cpu |
| 40 | + @info "Training on CPU" |
| 41 | + end |
| 42 | + |
| 43 | + # LOAD DATA |
| 44 | + data = Cora.dataset() |
| 45 | + g = FeaturedGraph(data.adjacency_list) |> device |
| 46 | + X = data.node_features |> device |
| 47 | + y = onehotbatch(data.node_labels, 1:data.num_classes) |> device |
| 48 | + train_ids = data.train_indices |> device |
| 49 | + val_ids = data.val_indices |> device |
| 50 | + test_ids = data.test_indices |> device |
| 51 | + ytrain = y[:,train_ids] |
| 52 | + |
| 53 | + nin, nhidden, nout = size(X,1), args.nhidden, data.num_classes |
| 54 | + |
| 55 | + ## DEFINE MODEL |
| 56 | + model = Chain(GCNConv(g, nin => nhidden, relu), |
| 57 | + Dropout(0.5), |
| 58 | + GCNConv(g, nhidden => nhidden, relu), |
| 59 | + Dense(nhidden, nout)) |> device |
| 60 | + |
| 61 | + ps = Flux.params(model) |
| 62 | + opt = ADAM(args.η) |
| 63 | + |
| 64 | + @info g |
| 65 | + |
| 66 | + ## LOGGING FUNCTION |
| 67 | + function report(epoch) |
| 68 | + train = eval_loss_accuracy(X, y, train_ids, model) |
| 69 | + test = eval_loss_accuracy(X, y, test_ids, model) |
| 70 | + println("Epoch: $epoch Train: $(train) Test: $(test)") |
| 71 | + end |
| 72 | + |
| 73 | + ## TRAINING |
| 74 | + report(0) |
| 75 | + for epoch in 1:args.epochs |
| 76 | + gs = Flux.gradient(ps) do |
| 77 | + ŷ = model(X) |
| 78 | + logitcrossentropy(ŷ[:,train_ids], ytrain) |
| 79 | + end |
| 80 | + |
| 81 | + Flux.Optimise.update!(opt, ps, gs) |
| 82 | + |
| 83 | + epoch % args.infotime == 0 && report(epoch) |
| 84 | + end |
| 85 | +end |
| 86 | + |
| 87 | +train(usecuda=false) |
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